Nader E Abedrabbo

• PhD Mechanical Engineering
• Engineer at General Motors Company

The selection of optimal operational parameters for drilling oil and gas wells is a complex dynamic problem that depends on multiple parameters. Numerous physical and mechanical processes such as rock cutting, friction, hydraulics, and different modes of vibrations, occur during drilling, which should be accounted for in numerical models. It is wid...

There exists considerable motivation to reduce vehicle weight through the adoption of lightweight materials while maintaining energy absorption and component integrity under crash conditions. Aluminium and magnesium alloys, advanced high-strength steels, and composites are all proposed candidates for replacing mild steel in automotive structures. I...

The performance of non-hydroformed and hydroformed structural steel tubes in component-level crash testing was investigated using both experimental and analytical techniques. In particular, the focus was on high-strength steels that may have potential to enhance crashworthiness of automobiles. Monolithic tubes made from multiple materials and wall...

In this paper, an optimization method linked with the finite element method is presented for developing forming parameters of the tube hydroforming (THF) process for several advanced high-strength steel (AHSS) materials. The goal of this research was to maximize formability by identifying the optimal internal hydraulic pressure and end-feed rate, w...

A temperature-dependent anisotropic material model was developed for two aluminum alloys AA5182-O and AA5754-O and their anisotropy parameters were established. A coupled thermo-mechanical finite element analysis of the forming process was then performed for the temperature range 25–260 °C (77–500 °F) at different strain rates. In the developed mod...

The temperature-dependent Barlat YLD96 anisotropic yield function developed previously [Forming of aluminum alloys at elevated temperatures – Part 1: Material characterization. Int. J. Plasticity, 2005a] was applied to the forming simulation of AA3003-H111 aluminum alloy sheets. The cutting-plane algorithm for the integration of a general class of...

A temperature-dependent anisotropic material model for use in a coupled thermo-mechanical finite element analysis of the forming of aluminum sheets was developed. The anisotropic properties of the aluminum alloy sheet AA3003-H111 were characterized for a range of temperatures 25–260 °C (77–500 °F) and for different strain rates. Material hardening...

An efficient integration algorithm for continuum damage based elastoplastic constitutive equations is implemented in LS-DYNA. The isotropic damage parameter is defined as the ratio of the damaged surface area over the total cross section area of the representative volume element. This parameter is incorporated into the integration algorithm as an i...

Temperature-dependant anisotropic material models for two types of automotive aluminum alloys (5754-O and 5182-O) were developed and implemented in LS-Dyna as a user material subroutine (UMAT) for coupled thermo-mechanical finite element analysis (FEA) of warm forming of aluminum alloys. The anisotropy coefficients of the Barlat YLD2000 plane stres...

Thesis (Ph. D.)--Michigan State University. Dept. of Mechanical Engineering, 2005. Includes bibliographical references (leaves 154-163).

In this paper, the wrinkling behavior of 6111-T4 aluminum alloys during sheet hydroforming process was numerically and experimentally investigated. In sheet hydroforming, one or both surfaces of the sheet metal are supported with a pressurized viscous fluid, while a punch forms the part. In sheet hydroforming the use of a matching female die is not...

The objective of this research was to numerically study the application of the sheet hydroforming process to a real-world complex automotive part. In sheet hydroforming, one or both surfaces of the sheet metal are supported with a pressurized viscous fluid to assist with the forming of the part where a female die is not required. The pressurized fl...

An approach is presented to optimize a tube hydroforming process using a Genetic Algorithm (GA) search method. The goal of the study is to maximize formability by identifying the optimal internal hydraulic pressure and feed rate while satisfying the forming limit diagram (FLD). The optimization software HEEDS is used in combination with the nonline...

The objectives of this research was to experimentally and numerically study the stamp hydroforming process as a means for shaping aluminum alloy sheets. In stamp hydroforming, one or both surfaces of the sheet metal are supported with a pressurized viscous fluid to assist with the stamping of the part thereby eliminating the need for a female die....